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The rocks actually occupy a much larger area; much of the Witwatersrand System is covered by later deposits, and the subsurface areal extent of Witwatersrand rocks has …
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the Witwatersrand gold could have formed only during the Archaean, after the emergence of continental life but before the rise of oxygen in the Earth's atmosphere.
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The world-class Witwatersrand gold deposit in South Africa has produced some 50 000 tonnes of gold since mining began in the late 1880s (Robb & Robb 1998). The gold is mostly hosted
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The Witwatersrand Basin occupies a central position on the Archaean Kaapvaal Craton (Fig. 2).The causes of its development and early evolution are linked with tectonic processes in and around this craton, whose history is subdivided into two main periods (de Wit et al., 1992).The first period (3.64–3.08 Ga) saw the initial formation of …
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The world's greatest deposit of gold is hosted by the Archaean Witwatersrand sedimentary basin, situated in the central portion of the Kaapvaal Craton of South Africa.
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Deposits formed throughout the last 3.8 billion years of the Earth's history preserve key evidence with which to test fundamental questions about the evolution of the Earth. ... microbeam analytical and petrological study of the main auriferous horizons in the Central Rand Group throughout the Witwatersrand Basin indicates that gold has been ...
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Geological and mineralogical specificity of the world's largest Witwatersrand gold deposit was defined by geodynamic processes in the Late Archean. The primary crust composed of felsic rocks ("gray gneisses") was intruded 2.9–3.1 Ga ago by mafic melts that gave rise to greenstone belts. This was followed by the appearance of long-lived …
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Studies of the morphology and other properties of the gold particles in the fossil placer gold deposits of the Witwatersrand provide fascinating glimpses of the conditions under which they were formed. In particular they indicate that in some areas primitive plant life on the deltas on which the gold was deposited acted not only like the ...
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Precipitation of the richest gold deposits could have been triggered by chemical reduction of the dissolved gold onto organic material in shallow lakes and pools. I conclude that …
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Studies of the morphology and other properties of the gold particles in the fossil placer gold deposits of the Witwatersrand provide fascinating glimpses of the conditions under which they were formed. In particular they indicate that in some areas primitive plant life on the deltas on which the gold was deposited acted not only like the legendary golden fleece …
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Abstract Analyses of gold particles from the Ventersdorp Contact Reef in the Klerksdorp and Carletonville goldfields of the Late Archaean Witwatersrand Basin reveal a wide range in Au, Ag and Hg concentrations of 80.9 to 92.9, 6.0 to 17.6, and 0.6 to 5.8 wt.%, respectively. However, individual gold particles are generally homogeneous. This …
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The Witwatersrand gold deposit is the largest in the world. Thermodynamic calculations show that such rich accumulations of gold could be linked to abundant volcanism, primitive life and the … Expand. 52. PDF. Save. Ages of altered granites adjoining the Witwatersrand Basin with implications for the origin of gold and uranium.
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Witwatersrand, ridge of gold-bearing rock mostly in Gauteng Province, South Africa.Its name means "Ridge of White Waters, in Afrikaans."The highland, which forms the watershed between the Vaal and Limpopo rivers, is about 100 km long and 37 km wide; its average elevation is about 1,700 meters. Its rich gold deposits, occurring in …
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The location of Lindum TSF is located 4.2 km south of the Dump 20 TSF which was studied by Zhang et al. (2023) (Fig. 1b). The Witwatersrand Basin is famous for its gold endowment, having produced ...
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The first recorded discovery of gold on the Witwatersrand was made by Jan Gerrit Bantjes in June 1884, on the farm Vogelstruisfontein, and was followed soon thereafter, in September, by the Struben brothers who uncovered the Confidence Reef on the farm Wilgespruit, near present-day Roodepoort. ... deposits had invariably proved to have a …
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Witwatersrand Gold Deposits. A special type of gold deposit is the Witwatersrand goldmine in South Africa, which is by far the biggest gold field in the world. About 40,000 tonnes of gold have already been extracted from it. The Witwatersrand goldmine is identified as a so-called mixed type of primary and secondary gold deposits.
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The amount extracted from the Witwatersrand Basin is estimated at over 40,000 tons of gold. The Witwatersrand Basin's gold deposits were formed around 2.8 billion years ago through hydrothermal and sedimentary processes. Layers of sediment, rich in gold, accumulated over time and were later compressed into the hard rock formations …
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South Africa's Witwatersrand Supergroup (WSG) gold deposits have produced over 48,000 metric tons of gold and have accounted for about 40% of the world's total historic production ().Attempts to date WSG gold mineralization remain equivocal, yielding a complex geochronology with ages that reflect multiple disturbances (2–9).
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hosted gold deposits, as erosional relics of a potentially much larger primary source of gold1,6. Gold in the Witwatersrand is enriched to mineable concentrations in thin quartz pebble beds ('reefs') that commonly extend over kilometers. These beds represent residual deposits on mature continental land surfaces, where river plains with gravels
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Witwatersrand, ridge of gold-bearing rock mostly in Gauteng province, South Africa.Its name means "Ridge of White Waters." The highland, which forms the watershed …
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In the discussion about conglomerate-hosted gold deposits, the controversy has mainly centred on whether the gold deposits of the Mesoarchaean Witwatersrand Basin were formed by (a) hydrothermal ...
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The Witwatersrand gold deposit is the largest in the world. Thermodynamic calculations show that such rich accumulations of gold could be linked to abundant volcanism, primitive life and the oxygen-free atmosphere of the Archaean. The Witwatersrand Basin in South Africa is one of the best-preserved records of fluvial …
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The Witwatersrand Basin in South Africa is one of the best-preserved records of fluvial sedimentation on an Archaean continent. The basin hosts the worlds biggest gold resource in thin pebble beds, but the process for gold enrichment is debated. Mechanical accumulation of gold particles from flowing river water is the prevailing hypothesis, yet …
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In 1852, the English prospector J.H. Davis discovered the first gold in the Witwatersrand, leading to the South African gold rush and the discovery of much more …
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another quartz-pebble-conglomerate gold deposit as rich as the Witwatersrand deposits remains highly unlikely because of the confluence of features necessary to create such a large endowment of gold. However, some smaller occur-rences do exist in the United States. Pyritic paleoplacers of sub-ore grade are found in the Deep Lake Group and
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The rocks actually occupy a much larger area; much of the Witwatersrand System is covered by later deposits, and the subsurface areal extent of Witwatersrand rocks has been delimited by exploratory geophysical and drilling studies because the Witwatersrand is of great economic importance owing to its valuable deposits of gold and uranium. In ...
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In 1852, the English prospector J.H. Davis discovered the first gold in the Witwatersrand, leading to the South African gold rush and the discovery of much more gold deposits within the basin.
WhatsApp: +86 18221755073
The Witwatersrand gold deposit is the largest in the world. Thermodynamic calculations show that such rich accumulations of gold could be linked to abundant volcanism, primitive life and the ...
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The Witwatersrand gold fields of South Africa account for more than a third of the world's total gold pro- ... stone gold deposit (i.e., Kalgoorlie, 2,000 t Au in five square.
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The mineralogy and geochemistry of Witwatersrand pyrite, gold, uranium and carbonaceous matter; ... similar to the world-famous conglomerate-hosted gold deposits of the Mesoarchean Witwatersrand Basin in South Africa. In the studied metaconglomerates from India, gold occurs as invisible inclusions in pyrite and as …
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